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Date: Wed, 24 Dec 2003 06:46:01 -0800 (PST)
From: Raj Mansa <mansa_dev@yahoo.com>
Subject: Netfilter 2.4.21 Kernel
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Hi,
I found this block of code in br_dev_queue_xmit() @
br_forward.c, after applying 'netfilter' patch for
2.4.21 kernel

Can someone explain what this block of code is doin?

#ifdef CONFIG_NETFILTER
        if (skb->nf_bridge)
                memcpy(skb->data - 16,
skb->nf_bridge->hh, 16);
#endif

1. What is 16 bytes here...? Ethernet hdr is just 14
bytes
2. Why the ethernet hdr is being overwritten with
nf_bridge->hh? what is there in nf_bridge->hh? and
when is nf_bridge being assigned this content.
3. If I remember correctly 'if' <condition> Fails for
ARP protocol and arp is untouched.

-Raj

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